Bethan Jelfs, customer service director for Arriva Trains Wales and Alison Thompson, chief operating officer of Network Rail Wales and Borders, said: “We are urging passengers to check before they travel this weekend, due to extreme weather across Wales and Borders.

"Storm Callum, predicted by the Met Office, is expected to cause serious flooding around the rail network and so Arriva Trains Wales and Network Rail have agreed to amend a number of services on Friday, Saturday and Sunday.

“To keep our colleagues and customers safe, with up to 200mm of rain set to fall over a 48-hour period, coupled with very high winds and high tides, we will be implementing an amended train service and emergency speed restrictions at key flood risk areas across our network.

“Particular areas at risk include the Cambrian coast, Swansea bay across to Carmarthen Bay and Black Bridge in Glantwymyn, Powys.

“We will be monitoring the weather closely, and engineers and mobile teams from both organisations will be on standby to respond to any issues which occur during the storm.

“Replacement road transport will be in place wherever possible and we will have additional team members to support at key locations but we urge people to check before travelling and be prepared for some short notice changes to journeys."

Arriva is also advising customers that road transport is subject to local road conditions and may also be affected by road closures.

A spokesman added: "Additionally, further route closures may occur during the course of the storm.

"Customers with tickets dated for travel on Friday 12th and Saturday 13th October are able to use their tickets on Sunday 14th and Monday 15th October."